1. Field of the Invention
This invention relates to an image-forming apparatus for forming a visible image on a recording medium by causing developer to be electrostatically attached thereto and, more particularly, to a mechanism for positioning a recording medium feed member and a charging electrode relative to each other in such image-forming apparatus.
2. Related Background Art
Japanese Patent Laid-open No. 60-250429 discloses an apparatus, which can form an image on a recording medium by feeding the medium with drive means. In this apparatus, a visual image of an original is formed to an enlarged scale on a whiteboard film fed out from a roll by transferring ink from an ink ribbon onto the whiteboard film by a thermal head.
As a technique like that noted above, there is a so-called electronic blackboard, which uses a plastic film in the form of an endless belt as display medium for copying information formed thereon.
The whiteboard film or plastic film in the electronic blackboard has semi-permanent life. Therefore, there is neither any concept of replacing such film nor any disclosed technique for replacing the film.
However, in an image-forming apparatus, in which a visible image is formed on recording medium like an endless belt driven for excursion by drive means by causing developer to be attached electrostatically on the medium, the medium has a predetermined life. That is, replacement with a new recording medium is necessary when a predetermined number of image formation cycles is reached.
Further, in the image-forming apparatus noted above, the recording medium and recording electrode should be spaced apart by a stringently controlled distance.
As noted above, the recording medium in the image-forming apparatus noted above should be replaced when a predetermined number of image formation cycles is reached. To permit smooth replacement, the recording medium is loaded in a support frame which is hinged or pivoted to an image-forming apparatus housing, and for replacement the support frame is opened form the housing. Since the support frame is pivotable relative to the housing, however, it is difficult to maintain a fixed distance between the recording medium and recording electrode.